Whole body protein kinetics were investigated in 13 subjects, children with edematous malnutrition (EM) and acute infection and compared with 14 controls, children with EM early in recovery with a primed, constant infusion of 13C-leucine and 15N2-urea in the fasted state. Calculations of rates of whole body protein synthesis, and breakdown were made using isotopic enrichments of serum 13C-leucine and the rate of urea turnover was used to estimate the rate of leucine oxidation. Protein synthesis and protein breakdown rates were lower in subjects than in controls (97 + 30 vs 153 + 67, p<O.O1 and 103 + 30 vs 16067 umoI Leu/kg/h, p<O.O1). No difference was found in the rate of leucine oxidation between the two groups. The absence of an expected increase in the rate of protein turnover during acute infection in EM implies a blunting of the acute phase response and suggestions for further work are made.